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Halogens Enhance Haze Pollution in China
Qinyi Li1, Xiao Fu2,3, Xiang Peng2
1Department of Atmospheric Chemistry and Climate, Institute of Physical Chemistry Rocasolano, CSIC, Madrid 28006, Spain.
Environmental Science & Technology
|September 30, 2021
Summary
Halogens, especially bromine, significantly worsen northern China
Area of Science:
- Atmospheric Chemistry
- Environmental Science
Background:
- Severe haze in northern China involves high fine aerosol loading, impacting health and ecosystems.
- Existing knowledge inadequately explains haze formation, despite observed reactive halogen species.
Purpose of the Study:
- To compile an anthropogenic bromine emission inventory.
- To quantify the collective impact of halogens on haze pollution in northern China.
Main Methods:
- Utilized the WRF-Chem regional model, updated with halogen chemistry and emissions.
- Validated the model with atmospheric pollutant and halogen measurements.
- Quantified halogen impacts on fine aerosol and secondary aerosol components.
Main Results:
- Halogens enhance fine aerosol loading in northern China by an average of 21%.
- Halogens significantly increase secondary organic aerosol (∼130%) and other secondary aerosols (∼20%).
- Halogen chemistry enhances atmospheric oxidants, with a notable contribution from bromine.
Conclusions:
- Anthropogenic halogens, particularly bromine, play a critical role in northern China's haze pollution.
- Increased recognition of halogen impacts is crucial for haze research and air quality management.
Keywords:
Anthropogenic bromine emissionHaze pollutionReactive halogen speciesSecondary aerosolWRF-ChemMore Related Videos
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